What is Complex Programmable Logic Device?
A complex programmable logic device (CPLD) is a logic device with fully programmable AND / OR arrays and macro cells. Macro cells are the main building blocks of a CPLD that contain complex logical operations and logic for implementing disjunctive normal form expressions. AND / OR arrays are completely reprogrammable and are responsible for performing various logic functions. Macro cells can also be defined as functional blocks that are responsible for executing sequential or combinatorial logic.
A complex programmable logic component is an innovative product compared to previous logic components such as programmable logic fields (PLA) and programmable array logic (PAL). The earlier logic modules were not programmable, so the logic was built by combining several logic modules. A CPLD has a complexity between PALs and field programmable gate arrays (FPGAs). It also has the architectural characteristics of PALs and FPGAs. The main difference between a CPLD and FPGA is that FPGAs are based on look-up tables, while CPLDs are based on see-of-gates.
The common characteristics of CPLDs and FPGAs are that they both have a large number of gates and flexible provisions for logic. One of the common features between CPLDs and PALs is the non-volatile configuration memory. CPLDs lead the programmable logic device market and offer numerous advantages such as advanced programming, low cost, non-volatile and easy-to-use functions.